diff --git a/common/render-dag.make b/common/render-dag.make
new file mode 100644
index 0000000..623f07f
--- /dev/null
+++ b/common/render-dag.make
@@ -0,0 +1,14 @@
+.PHONY: all clean
+
+all: rendered-dag.png clean
+
+rendered-dag.png: rendered-dag.dot
+	dot -Tpng $< -o $@
+
+rendered-dag.dot: Makefile
+	make -Bnd -f $< | make2graph > $@
+
+clean:
+	rm -f rendered-dag.dot
+
+# vi: ft=make
diff --git a/flake.nix b/flake.nix
index f994536..4b56a91 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,11 +4,11 @@
   inputs.flake-utils.url = "github:numtide/flake-utils";
 
   outputs = { self, nixpkgs, flake-utils }:
-    flake-utils.lib.eachDefaultSystem (system: let
-      pkgs = nixpkgs.legacyPackages.${system};
-    in {
-      devShells.default = pkgs.mkShell {
-        packages = [ pkgs.gnumake ];
-      };
-    });
+    flake-utils.lib.eachDefaultSystem (system:
+      let pkgs = nixpkgs.legacyPackages.${system};
+      in {
+        devShells.default = pkgs.mkShell {
+          packages = [ pkgs.gnumake pkgs.makefile2graph pkgs.graphviz ];
+        };
+      });
 }